Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
Any air vents on the cylinder flow or return? Have you tried cracking the nuts on the cylinder to vent any air?
I hate it when this is what needs to be done. All seized and it ends up moving the flange on the coil and that
Starts to leak. Although it's a new install.
Coincidentally, what do people do to fix the problem I mentioned above
Well as I said with the motor off the three port all rads get hot so not blocked microbore.
Must be the coil
The 3 port is the wrong way round.
Could a bit of lagging get in the cylinder
Reply to the thread, titled "Does it sound like air to you?? I'm at a loss" which is posted in Air Sourced Heat Pumps Advice Forum on Plumbers Forums.
We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.